Tamed creatures cannot attack their owner - if you attack your tamed creature enough times, the taming ribbon will break and they can finally attack back, but that doesn't sound like what's going on. Currently, there's no way to revive creatures - that's a planned change, but if sally died she'd be gone for good. The teeth are just a daily drop for swampjaws.
As for grudges, they do fade over a few days, but yes, creatures can remember you attacked them or stole their eggs.